Come valuta cos ((2pi) / 3) ?
Risposta:
-1/2
Spiegazione:
The angle (2pi)/3" is in the 2nd quadrant "
where the cos ratio has a negative value.The related 'acute angle' to (2pi)/3 =( pi -(2pi)/3) = pi/3
rArr cos((2pi)/3) = - cos(pi/3)
and using the color(blue)" Exact value triangle"
cos((2pi)/3) = - cos(pi/3) = -1/2